OP, if you're getting a combination of P0171/0174 or P0172/0175 check your gas cap....that's what fixed it for me.

 

So, went to the dealer today, was told that the aftermarket MAF sensor I placed on the car was not performing to spec. So moral of the story, but once, cry once and go with the OEM on this. I will inform if the code comes back, but hopefully this solves the issue. Thanks for your help guys!

 

Glad you got it fixed. Turns out the gas cap did NOT fix the issue after all....the kid informed me today the CEL came back. I've made an appointment at the dealer for Monday but going to try and clean the MAF tomorrow (she has to work today).

 

Yeap, only reason I replaced the MAF to begin with was because of the P0101 code where the MAF was already probably going bad. Nevertheless, the P0175/P0172 remained, so it seems the replacement aftermarket MAF just wasn't good enough. So hopefully this helps!